1. Field of the Invention
The present invention relates to a light emitting diode package, and more particularly, to a light emitting diode package using a thermoelectric element.
2. Description of the Related Art
A light emitting diode (hereinafter, referred to as an “LED”) refers to a semiconductor device having a p-n junction structure in which minority carriers (electrons or holes) are injected and light is emitted through recombination of the carriers. A variety of light emitting sources can be constructed by changing material of compound semiconductors such as GaAs, AlGaAs, GaN, InGaN and AlGaInP to provide light having various colors. The luminance of an LED is proportional to a current applied to a light emitting chip thereof, and the current applied to the light emitting chip is proportional to heat generated from the light emitting chip. Thus, a high current should be applied to increase the luminance of an LED. However, since the light emitting chip may be damaged due to heat generated therefrom, there is a problem in that the current cannot be increased infinitely. That is, as the current applied to the light emitting chip increases, the heat generated therefrom increases.
FIG. 5 is a sectional view of a conventional light emitting diode package that comprises a substrate, at least one light emitting chip mounted on the substrate, and a pair of lead frames. The substrate is formed of an insulating resin and has a reflective portion formed to surround the light emitting chip. Both electrodes of the light emitting chip are connected to the respective frames through conductive wires. The lead frames are electrically and thermally isolated from each other.
In the conventional light emitting diode package constructed as above, heat generated from the light emitting chip is dissipated through the lead frames. However, heat dissipation only through the lead frames of the light emitting diode package has a limitation on the amount of heat dissipation. Particularly, in case of recently developed high power light emitting diode packages, heat conduction only through lead frames is not sufficient for heat dissipation. That is, if a heat dissipation structure is not properly provided in the light emitting diode package, the heat generated from the light emitting chip cannot be efficiently dissipated, thereby causing a problem in that the service life of the light emitting chip is shortened.